1. Field of the Invention
The present invention pertains to a surgical instrument and, more particularly, pertains to a biopsy needle which can either be disposable or reusable.
2. Description of Prior Art
The prior art biopsy needles have all presented some type of drawbacks when used by the physician or surgeon, and which are particularly less than desirable. Some prior art instruments are disposable and cast with very few structural details attended to, with the result that the interlocking between the stylet and the cannula provides for considerable play and the instrument can come apart in the user's hands, resulting in injury not only to the patient but more so to the user by the sharp metal edges poking upwards into the physician's hands. Other prior art devices have some form of interlocking structure but the interlocking structure is not positive, resulting in play between the cannula and stylet during the process of incision into the patient resulting in considerable discomfort. Other types of prior art structures have numerous components which during surgery are not practical in utilization by the user due to the screwing and unscrewing of the fittings.
More importantly, all of the prior art devices have grips which do not really fit into the physician's hand to provide for positive gripping by the physician but have grips which are required to be engaged by the physician in a negative way making the process of biopsy as uncomfortable to the physician/surgeon using the sternum needle as to the patient. The prior art has failed to recognize that the handles of a biopsy needle must securely engage into the physician's or surgeon's palm for optimum control of the instrument during a biopsy. It is also necessary that the sytlet and cannula be engaged to each other during the biopsy process for providing total control to the physician or surgeon.
The present invention overcomes the disadvantages of prior art references by providing a biopsy needle having a winged handle, detent locking between the stylet and cannula, and an adjustable threaded depth stop.